Filter refunded status

[JStockton-Kishmish]

Issue: #590

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Description

Apply the woocommerce_order_fully_refunded_status filter to allow using wc_refund_payment() for voiding a transaction programmatically. The only issue that I see with doing so currently is that the order status gets changed which, in my case, I do not want.

Steps to Test

Create 2 orders both using the Paypal gateway in authorize mode . Refund them by calling the following script:

<?php
require_once('wp-load.php');

$order_1 = wc_get_order(1234); // Replace 1234 with the post_ID of the first order
$order_2 = wc_get_order(1235); // Replace 1235 with the post_ID of the second order

wc_refund_payment($order_1);
add_filter('woocommerce_order_fully_refunded_status', '__return_false');
wc_refund_payment($order_2);

Observe that $order_1 is now in the refunded status whereas $order_2 remained in the status it was at in the beginning, but both authorizations were voided in Paypal.

Changelog Entry

Allow filtering of refunded status on voids